def generate_ray(self, sample):
"""Generate a Ray from the camera."""
# Generate raster and camera samples
p_ras = Point(sample.image_x, sample.image_y, 0)
p_camera = self.raster_to_camera(p_ras)
ray = Ray(Point(0, 0, 0),
normalize(Vector.from_point(p_camera)),
0.0,
float('inf'))
# Modify ray for depth of field
if self.lens_radius > 0.0:
# Sample point on lens
lens_u, lens_v = concentric_sample_disk(sample.lens_u,
sample.lens_v)
lens_u *= self.lens_radius
lens_v *= self.lens_radius
# Compute point on plane of focus
ft = self.focal_distance / ray.d.z
p_focus = ray(ft)
# Update ray for effect of lens
ray.o = Point(lens_u, lens_v, 0.0)
ray.d = normalize(p_focus - ray.o)
ray.time = sample.time
ray = self.camera_to_world(ray)
return 1.0, ray
def generate_ray(self, sample):
"""Generate a Ray from the camera."""
# Generate raster and camera samples
p_ras = Point(sample.image_x, sample.image_y, 0)
p_camera = self.raster_to_camera(p_ras)
ray = Ray(Point(0, 0, 0), normalize(Vector.from_point(p_camera)), 0.0,
float('inf'))
# Modify ray for depth of field
if self.lens_radius > 0.0:
# Sample point on lens
lens_u, lens_v = concentric_sample_disk(sample.lens_u,
sample.lens_v)
lens_u *= self.lens_radius
lens_v *= self.lens_radius
# Compute point on plane of focus
ft = self.focal_distance / ray.d.z
p_focus = ray(ft)
# Update ray for effect of lens
ray.o = Point(lens_u, lens_v, 0.0)
ray.d = normalize(p_focus - ray.o)
ray.time = sample.time
ray = self.camera_to_world(ray)
return 1.0, ray
